O182: Tag localisation vs wire localisation: which is the more effective technique for localising non palpable breast lesions?

Abstract Introduction Following the expansion of breast screening programmes, non-palpable lesions comprise a challenge for accurate localisation. Placement of wires has been the historic gold standard of care. We aimed to compare wire-guided localisation (WGL) to radiofrequency identification system (RFID) LOCalizer(Hologic) with regards to resection margins and complications. Methods Data was collected retrospectively on patients who underwent breast conserving surgery for malignancy following localisation with LOCalizer RFID system or wire, in Beaumont Breast Centre, from January 2018 to March 2023. Lesion type, size, specimen weight, resection margins and complications were recorded and analysed. Results 690 were included in the study. 391 (57%) had a pre-operative diagnosis of malignancy: 88 in RFID tag guided localisation (TGL), 129 in mammogram wire guided localisation (MG-WGL) and 174 in ultrasound (US-WGL). The remaining had therapeutic excisional biopsy in which 18 (6%) were upgraded to in situ or invasive. Positive surgical margins were; US-WGL was 24% (43), MG-WGL was 23% (34) and TGL was 12% (11). Average tumour size was: 20.3mm US-WGL, 13.0mm MG-WGL, 18.3mm TGL. Average specimen weight for malignant cases were 33.8g US-WGL, 43.5g MG-WGL and 40.7g TGL. No significant complications were recorded in either group, however, a second localisation procedure was required for 14 patients in the TGL group and 10 patients in the WGL group. Conclusion TGL is a safe and effective alternative technique which allows greater flexibility in scheduling and increased efficiency. It has a learning curve which accounts for the slightly higher complication rate identified.